As a practicing Catholic (and a hypocrite one at that), yes, God forgives every imaginable sin starting from Adam and Eve until the last person born on this Earth (and universe). There are few things needed before forgiveness happens. One should be repentant and genuinely feel sorry for his or her own sin. One corrects his or her action(s) and reverses the result of the sin as much as possible, which may include turning oneself to the authorities if it's a severe crime. Lastly, one has to confess their sins to a priest and follow his advice and penance. If all of these are met, then the priest will absolve the penitent.
Suicide, on the other hand, is a different matter. It's a sin that you can't confess because it's something that a person will do in the future. Confession will only work if the sins are done in the past, not present or future. However, I do believe that a person with mental illness or have some kind of depression are forgiven because of their state of mind. It's important to note that the Church hasn't declared anyone to hell, whether it be Judas, Hitler, Mao or Stalin. We don't know if there's anyone in hell, but divine or holy revelations to saints have shown that there are plenty of sinners in there, but it's not mandatory to believe in these revelations.
Yes, God to me forgives every sins. May He forgive everyone's sins as long as they feel sorry and correct their actions and be a genuinely good person starting from the day they realized that they strayed from good.
Disclaimer:
I know that there are plenty of atheists and God-haters out there, but I simply answered OP's questions. I know why you hate God, and I can't blame you. If I die and saw Him, I'll ask tough questions that about our earthly sufferings that may be contradicting His eternal and infinite love.